DC Comics' Elseworlds and multiverse comics are among their best written and most famous stories, thanks to their self-contained nature. Rather than buy into a big, ongoing narrative, casual readers can pick up these often seminal works of fiction and see their favorite heroes in action. However, it has become increasingly common for these stories to be acknowledged in or outright change ongoing continuity in the DCU.

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These multiverse comics can shape continuity in several ways. It's common for newer depiction of heroes to become the norm. Some canon stories even adopt new layers to a character from the multiverse. Stories like Watchmen have earned a reputation for the darker, edgier spin on the superhero genre. It's because of their popularity that these multiversal stories can change the direction of DC's entire superhero universe.

10 Multiversity Laid The Groundwork For Two Separate Eras Of DC

The Justice League Incarnate from The Multiversity

The New 52's Multiversity depicted heroes from across the DC multiverse coming together. It formed the Justice League Incarnate and laid the groundwork for the beloved post-Crisis Superman to return in what would later be DC Rebirth.

Multiversity (by Grant Morrison, Ivan Reis & Joe Prado) was originally a multiversal team-up book, but its team became pivotal to later DC continuity. It was the Justice League Incarnate who first battled the Great Darkness in a bid to contain it. It also provided an end to Flashpoint Batman.

9 Superman And The Authority Teamed The Man Of Steel With Wildstorm's Heroes

An older Superman studies villains in DC Comics

Grant Morrison and Mikel Janin's Superman and the Authority brought together DC's greatest hero with the Wildstorm team, The Authority. The story helped establish the Authority as part of canon, which proved vital since they would later help Superman go to Warworld.

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Superman and the Authority remains memorable for several reasons. Not only is it Grant Morrison's last contracted work with DC, it's also is the first team-up of Superman and Manchester Black. The series has interesting status, incorporating Elseworlds themes, yet existing within continuity.

8 Gotham By Gaslight Helped Start The Trend Of Batmen Throughout The Ages

Gotham by Gaslight Batman and newspaper heading "Bat Haunts City"

For most of Batman's existence, fans believed there was only one, definitive version of The Dark Knight. After Gotham By Gaslight, DC took an interest in exploring the idea of different Batmen throughout historic eras. The Victorian era Batman was often used as a template.

Now, it's a part of established Batman canon that different versions of the hero have existed throughout history. Scott Snyder's Justice League even established that Gotham By Gaslight existed within the multiverse, although it was swiftly wiped out by Perpetua.

7 Injustice Helped Reignite The Evil Superman Trope

Superman holding a dead Lois Lane in his arms in the Injustice comics

Although "evil Superman" is an idea almost as old as the character himself, only one story can lay claim to the definitive evil Superman comic. Injustice — based on the video game — lit a match, and soon, the evil Superman trope found its way into various media, including the DCEU.

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Injustice presented such a definitive "dark Superman" story that fans now use the term "Injustice Superman" as a blanket term for any evil Superman. It has also been established that the Injustice continuity exists within the DC multiverse.

6 Kingdom Come Gave Readers An Idea For What The Future Holds

Superman leading the Justice League in comic book art for Kingdom Come.

Initially an Elseworlds tale that gave readers a glimpse of a possible DC future, Kingdom Come soon seeped into the main DC continuity. Not only did the likes of Magog and Kingdom Come Superman show up in canon comics but there was even a soft sequel, "Thy Kingdom Come."

To fans, Kingdom Come is the de facto concluding chapter on several main line heroes' stories. The comic is a perfect swan song for the publisher's greatest heroes. Additionally, homages and references to Kingdom Come can be found throughout later DC continuity and stories.

5 Green Lantern: Far Sector Introduced The Latest Emerald Warrior

Green Lantern: Far Sector Jo Mullein

Green Lantern: Far Sector (J.K. Jemisin & Jamal Campbell) introduced readers to Jo Mullein, a new spin on the Green Lantern. Originally a part of DC's Young Animal imprint, this comic was a solo, out of continuity Green Lantern detective story that followed a secret member of the corps.

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The Young Animal imprint became one of several attempts to duplicate the Vertigo tone, but in the case of Far Sector, DC decided it should be canon. Jo Mullein is now slated to be a key Green Lantern going forward, and is the corps member for her Future State Justice League team.

4 Harley Quinn's Comic Debut Was In The Batman Animated Series Comic

Harley Quinn and Poison Ivy point weapons at Batgirl

Debuting in Batman: The Animated Series, Harley Quinn's first print appearance was in the alternate continuity series The Batman Adventures #12 by Kelley Puckett, Mike Parobeck, Rick Burchett, Rick Taylor, and Tim Harkins. This series was a continuation of the DCAU version of Batman and Gotham and held true to the series.

When it was clear Harley Quinn was the breakout hit of BTAS, she exploded into the DCU and resumed the same role she had in the show. Harley went on to become one of DC's biggest characters over the next two decades, receiving numerous solo series and making plenty of memorable appearances.

3 The Dark Knight Returns Redefined Batman For Decades

Batman punches Superman in Frank Miller's The Dark Knight Returns in DC Comics

Few Elseworlds or even canon stories have redefined a character as suddenly as The Dark Knight Returns did for Batman. For much of his history, Batman had been an unremarkable hero, mostly relegated to done-in-one stories and team-up books like World's Finest.

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The Dark Knight Returns completely revamped Batman. Thanks to the writing of Frank Miller, Batman was reimagined from the basic street level hero to a vigilante who became far more vital to DC. Subsequent writers, knowingly or not, soon began incorporating Frank Miller's take on Batman.

2 The Killing Joke Is Basically Canon

Joker laughing in Batman: The Killing Joke.

Alan Moore and Brian Bolland's The Killing Joke proved to be one of his most impactful stories, both in comics and mainstream pop culture. Originally meant to be a darker spin for adults who had read comics in the '60s, the Elseworlds comic has slowly but surely been absorbed into canon.

The Killing Joke was also one of several comics that altered the tone and direction of Batman comics. It also set the foundation for Batgirl becoming Oracle. Despite Moore never intending for it to be, The Killing Joke was basically canon. It even led to a sequel in Three Jokers and a line of similar comics in One Bad Day.

1 Watchmen Ended Up Reshaping DC's Entire Continuity

An image of the main Watchmen characters from DC Comics

The effects of Watchmen took a long time to start affecting canon, but when it did, it made quite the impact. Key details from Watchmen were planted in DC's continuity and sown around Rebirth, which included "The Button," a story that focused on Comedian's button.

It was later revealed through comics like Doomsday Clock that Doctor Manhattan had crossed into DC continuity and had even caused the New 52 reboot. Because of this retcon, Manhattan became responsible for the entirety of DC Comics' continuity from 2011 to 2019, making Watchmen canon.

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